1. Field of the Invention
The field of art to which this invention pertains is the solid bed adsorptive separation of components of a fluid stream. More specifically, the invention relates to process for separating a saccharide from an aqueous solution of saccharides by employing an adsorbent comprising an ion exchange resin.
2. Description of the Prior Art
It is known in the separation art that certain ion exchange resins can be used in separating components from a fluid mixture, particularly a saccharide from an aqueous solution of saccharides. Examples of such art are U.S. Pat. Nos. 4,025,357; 4,022,637; 3,928,193; 3,817,787, 3,806,363; 3,692,582; 3,416,961; 3,184,334; 3,174,876; 3,044,906; 3,044,904; and 2,813,810. Common ion exchange resins used in the prior art processes are alkali metal and alkaline earth metal salts of a polystyrene sulfonate cation exchange resin cross-coupled with divinyl benzene. It is also known to the art to periodically backflush the entire resin bed so as to accomplish uniform packing or homogeneity of resin particle size throughout the column (U.S. Pat. No. 3,928,193) or to remove accumulated dirt, etc. (U.S. Pat. No. 3,416,961). It is further known to integrate a continuous backflushing zone into a simulated moving bed scheme such as that set forth in D. B. Broughton U.S. Pat. No. 2,985,589.
The principal of the simulated moving bed to continuously separate, in liquid phase, a saccharide from a liquid feed mixture of saccharides by contact with a solid inorganic sorbent comprising particles of crystalline aluminosilicate or zeolite is also known to the art via U.S. Pat. No. 4,157,267. The simulated moving bed functions by periodically advancing through the column of adsorbent the various points of introducing and withdrawing the liquid streams.
I have discovered a process that enables the use of an ion exchange resin in the simulated moving bed scheme by the integration of a system of intermittent backflushing into such scheme.